Paving Cape Cod

Assessing Impervious Surfaces on Cape Cod

The major focus of the Paving Cape Cod project is to demarcate the extent of impervious surfaces on Cape Cod and to identify their growing role in the natural environment. 

Impervious surfaces, along with septic systems, are among the primary sources of nonpoint source pollution on Cape Cod. Nonpoint source pollution, unlike pollution from industrial sources and sewage treatment plants, originates from Impervious surfaces include all paved roads and paths as well as buildings, bridges, recreational courts, pools, runways, tanks, paved driveways and parking lots. Rainwater washes off these surfaces and can carry toxic materials such as heavy metals, antifreeze, gas, oil, plastic, pet waste, rubber and other items. Accumulated pollutants are directed to storm drains, fresh and salt-water bodies, rivers, streams and wetlands. On Cape Cod, these nonpoint pollutants may be the leading cause of water quality degradation.

In general, if the area of impervious surfaces is less than six percent of the land area, the degradation of water supplies is usually not significant. If the area of impervious surfaces is more than this amount than water quality is likely to be affected.

Over the last few decades, Cape Cod (Barnstable County) has had one of the highest rates of population growth in the US. This growth has resulted in more of the land being paved or built upon. The increase in the area of paved or impermeable surfaces means that towns on Cape Cod must pay increasing attention to the degradation of once clean ground water resources that are otherwise dwindling.

The goals of the Paving Cape Cod project were:

• Impervious Surfaces
  to develop a map of the impervious surfaces of Cape Cod
• Future Buildout
  to conduct an analysis that will allow us to predict where new impervious surfaces are likely to occur as Cape Cod approaches build out
• Pollution Hot Spots
  to define the current local “hot spots” of nonpoint source pollution due to impervious surfaces

©Woods Hole Research Center, 2006